Telephone and wireless-telegraphy installation



L. N. BRILLOUIN. TEL EPHONE AND wmmss TELEGRAPHY"INSTALLATION.

v APPLICATION FILED APR. 25, I918. 1 ,4Q4,574 Patented Jan. 24, 1922.

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Z6 072/ @1372 Zza gvi L. N. BRILLOUIN. TELEPHONE AND WIIRELESSTELEGRAPHY INSTALLATION.

APPLICATION FILED APR-2521918- 'Patented Jan. 24, 1922.

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fivemior Z6070 (1612970 550 u an/ wzekse as arrange such installationsso as v LEON NICOLAS BRILLOUIN, OFIARIS, FRANCE.

TELEPHONE AND WIRELESS-TELEGRAPHY INSTALLATION.

Specification of Letters Patent. Patented Jan 24 1922 Application filedApril 25, 1918. Serial No. 230,795.

To all whom it may concern:

Be it known that I, LnoN NICOLAS BR L- LoUIN, citizen of the FrenchRepublic, residing at Paris, France, have invented certain new anduseful Improvements in Telephone and Wireless-Telegraphy Installations,of which the following is a specification.

This invention relates to telephone and telegraph installations and moreparticularly b to wireless telegraphy, which form the sub- 'ect of theUnited States patent application lVo. 174,633 filed on the 13th June1917 by Brillouin and Beauvais which mainly consists in inserting acondenser into each of the connections of the electrodes to each other,and using as an amplifier at the receiving stations of suchinstallations, a number of audions or repeaters each comprising afilament heated by an electric current and two different electrodes, andin connecting the second electrode or plate of one audion b to the firstelectrode or grid of the next audion, and the first electrode or grid ofthe first a-udion to the line, in connecting moreover the secondelectrodes or plates of each audion by means of a resistance to one ofthe poles of a source of current.

The invention has for its main object to to avoid the production ofinternal resonance, and so as to ensure amplification of any waves whichthey receive, whatever be their length, with or without heterodyning.The heterodyning can occur when the receiving apparatus is almostsynchronized for the lengths of external sustained waves to be received.Such external sustained waves then generate in the apparatus internalWaves which are almost synchronized with the external waves. Thecombined effects of the external wavesand the internal waves producebeats such as are produced in a heterodyne system. These beats areaudible in'the telephone. The invention mainly consists in connecting,by means of a suitable capacity, the first electrode or the grid of thefirst audion of such installations to the second electrode or the plateof another suitably selected audion. The invention comprises otherarrangements, more particularly referred to hereinafter.

In the accompanying drawing, by way of example:

Fig. 1 shows diagrammatically a wireless telegraphy receiving stationarranged in accordance with a first method of carrying out theinvention;

Fig. 2 shows diagrammatically a Wire'- less telegraphy receiving stationarranged in accordance with a second method of carrying out theinvention.

First of all, and in accordance withthe application hereinbeforereferred to, a numerof audions a c a a, is taken each comprising afilament 10, 20, 30, 40, a first electrode or grid 100, 200, 300, 400next to the filament and a second electrode or plate 1 2,013 4,separated from the filament by the gri v A source of electricity, forinstance a battery b, is taken, intended to supply the current forheating the filaments 10, 20, 30, 40 of the audions a a a a, and thesaid filaments are connected to the terminals of the said sourceofelectricity, the connection eing in parallel.

Another source of electricity 0 is provided, intended to give a tensionV in the plates 1, 2, 3, 4. One of the terminals of the said source 0 isconnected to the terminal of opposite sign of the sourceof electricity6, and the plates 1, 2, 3, 4 are connected to the other pole of the saidsource of electricity 0, a resistance d d d being inserted between saidother pole and each of the said plates, with the exception of that ofthe last audion.

One of the receiving terminals 6 of the installation which is adapted tobe connected to any known form of radio receiver is connected to thatpole of the source b, which is connected to the source 0, and the otherre. ceiving terminal e ,'whichis adapted to be connected to the otherterminal of the radio receiver, is connected to the grid 100 of thefirst audion, a condenser 7 being preferably inserted between the saidtermlnal and the said grid.

The plate 1 of the first audion is connected to the grid 200 of thesecond audion, a condenser f being inserted between the said plate andgrid. Identical connections are made between the plates. and the gridsof the next audions.

The resistance inserted between the plate 4: of the the last audion, andthe source ofelectricity 0, is replaced by a telephone instrument g.

Each grid is then connected, by means of a resistance 7Z1, 7?, if, 72,either to the source of current I) or, still better, to a potentiometerj shunted acrossthe terminals of audion in accordance with the length of"a certain delay an a source of current It, one of the terminals ofwhich is connected to one of the terminals, preferably to the positiveterminal, of the'source of current Z).

Nevertheless, carev must be taken, when connecting such an installation,to avoid creation of any reaction capacity that acts on any otherelement than the grid of the first audion. It is therefore advisable notonly to avoid any auxiliary connection that audion is then connected bymeans of a capacity- Z to a plate such as the plate 2, 3

or t or one of the following audions.

The capacity Z is preferably arranged, so that its value may be modifiedat will, and also so that it may beconnected, according tocircumstances'to the plate of any one of the audions a, a a

It is necessary to point out that when the value of the capacity Z isincreased, there is first produced an increase of the amplification,then heterodyning, and that by regulating the capacit Z regulation ofthe apparatus may be e ected in a very simple manner.

It is however impossible to select any audion, the plate of which is tobe connected by the capacity Z to the grid 100 of the first audion. Ifthe audion is wrongly selected, either heterodyning does not take place,or the heterod nmg takes place with (l suddenly and it is necessarysubsequently to reduce'the value of the capacity Z considerably in orderto ship the heterodyning.

n the contrary, if the audion is properly selected, the heterod ningtakes place gradually and without do ay, and it .ceases to take place assoon as the capacity Z is brought to a value slightly below that forwhich the heterodyning began to take place.

For the choice of the audion, it must be pointed out that a given audiondoes not ensure heterodyning for wave lengths smaller than a given wavelength, and that for wave lengths exceeding a given value, theheterodyning takes place suddenly and with a delay.

It is therefore necessary to choose the Wave to be received, bearing inmind'that' as the lengths of wave increase, it is necessary to take theaudions in an order depending on their order number, and also on thetelephone,

rename fact whether this order number is an even or an odd number.

It is advisable to choose suitably, on the one hand, the resistance hwhich connects the grid of the audion to the installation, the plate ofwhich is connected by the capacity Z to the grid of the first andion,

to the plate of the last audion (a in the construction shown in Fig. 2},and in addition are used the following arrangements;

Between vthe terminals of the telephone 9 which is inserted betweentheplate of the last audion and the positive pole of the high voltagesource of electricity 0the said telephone may be moreover replacedeither by the primary of a transformer, the secondary of which isconnected to the or by any desired suitable measuring instrumentisinserted a capacity g and between the plate of the last au'dion and thetelephone gor its substituteds inserted a resistance and a suitableself-inductance coil 9 In this way it-is possible to produceheterodyning for any desired lengths of sustained waves, from thesmallest to the lar est.

preceding audions in the series, and a suitable capacity connecting thegrid of the first audion to the plate of another audion of the series.

2. A wireless receiving system comprising receiver terminals, anamplifier embodying a series of audions each embodying a filament, agrid, and a plate, a circuit connecting the grid of the first audion toone of the receiver terminals, circuits connecting the grids of otheraudions to the respective plates of the preceding audions in the series,and a variable capacity connecting the grid of the first audion to theplate of another audion of the series.

3. A Wireless receiving system comprising receiver terminals, a seriesof audions each comprising a filament, a grid and a plate, a circuitconnecting the grid of the first audion to one of the receiverterminals, circuits connecting the grids of the other audions to therespective plates of the preceding audionsin the series, and a suitablecapacity adapted to connect the grid of the first audion to the plate ofanother audion of the series.

4. A wireless receiving system comprising receiver terminals, a seriesof audions each comprising a filament, a grid and a plate, a circuitconnecting the grid of the first audion to one of the receiverterminals,circuits connecting the grids of the other audions to the respectiveplates of the preceding audions in the series, and a variable capacityconnecting the grid of the first'audion to the plate of. another audionof the series, the latter audion being so selected that heterodyningtakes place gradually and with delay and ceases when the capacity isreduced to a value slightly below that at which heterodyning commences.

5. A wlreless receiving system comprising receiver terminals, a seriesof audions each 1 comprising a filament, a grid, and a plate, a

circuit connecting the grid of the first audion -to-one of the receiverterminals, a source of current supply for the filaments of theaudions,'another source of current supply of given voltage, resistancesconnecting the latter source of current supply to the-plates of theaudions, va circuit connecting the grid of the first audion to one ofthe. receiver terminals, circuits connecting the grids of the otheraudions to the respective plates of the preceding audions in the series,and a suit- I audion to the receiver terminals, a series of audionseachable capacity connecting the grid of the first series.

6. A wireless recelvmg system comprising plate of another audion of theI embodying a filament, a grid, and a plate, a

. necting the grid of the first audion to a plate of another audion-ofthe series, the said resistance and the capacity being of such relativevalue that they will avoid reduction of amplification and will alsoprevent singing.

7. A wireless receiving system comprising receiver terminals, a seriesof audions each comprising a filament, a grid, and a plate, a source ofcurrent supply connected to the filaments of the audions, another sourceof current supply, resistances connecting the latter source of currentsupply to the grids of the audions, the grid of the first audion beingconnected to one of the receiver terminals, circuits connecting thegrids of the other audions to the plates of the preceding audions in theseries, a capacity connecting the grid of the first audion to the plateof the last audion in the series, and a telephone circuit connected tothe plate of the last anclion, said telephone circuit containing aresistance and a self inductance coil in series with the telephone, andalso containing a capacity which shunts the telephone.

In testimony whereof I have'hereunto set my hand in presence of twosubscribing witnesses.

' V Witnesses:

CHAS. P. PREssLY, PAUL BLUM.

